The Clash were legends, not sell outs. If you bothered to listen to Rock the Casbah, the lyrics. It's a smite that slipped through the censors.
Emo? Don't ever compare that overprivileged, whitney, domesticated, generic, pathetic music to punk rock. You can't decide, let me do it for you. Punk doesn't want you!
Punk isn't about how you got messed with in high school, or how you can't be perfect for your parents, or wearing clothes from Hot Topic, or eating what the radio and the media is cramming down your throat.
It's the opposite of all of that. Its about what you did about it, not "Poor me, I'm so depressed about my mediocre life." Take your life under your control, make your own moves, statements, whatever. Nothing is punk rock about Panic at the Disco, 30 Seconds to Mars, My Chem, or Simple Plan or any of that packaged rebellion they are selling now. (By packaged rebellion I mean that most of those bands are hired guns. They spin a back story about them, run it through the media grinder, and put these guys on tour. They are all musicians that are put together by a label to generate money. Half of them didn't even know each other prior to becoming a band.)
The Clash broke through the media, so did The Ramones, Blondie, The Talking Heads, The Sex Pistols, GBH, and a slew of bands from that era. If it wasn't for bands like that you wouldn't have half of the bands that were directly influenced by them. Does that make them all sell outs?
Please tell anyone left from that era they aren't punk rock, and I can surely say with the utmost confidence you'll be receiving a waffle stomper up your backside.
Blondie wrote the Tide is High, a reggae tune, that charted. Still, Debra Harry carries more respect than any of you or myself in the punk community I can guarantee you.
Look into the bands that started this, and what they were about. Everything then was either Progressive rock, Disco or pop. Metal was in the same boat, and the media tried to push that to the side, too. None of it worked. Why? Because Punk and metal aren't designs created by anyone individual to make money.
They were a bunch of ticked off people, who were tired of the run of the mill junk they were being pedaled. So they did it themselves, and made their own rules for music, life, work, and society.
Read some stuff Rollins wrote, or Biafra, or Ian Mackay. Listen to those bands from then. Minor Threat, Bad Brains, Jody Fosters Army, Suicidal Tendencies, Dead Kennedys, D.R.I., Sick Of It All, Black Flag, Agnostic Front.
Even some of the more recent stuff like Bad Religion (who really have been around a long time, and aren't all that recent, but they are still making awesome music), Pennywise, NOFX, Anti-Flag, Rise Against, No Use For a Name, The Bouncing Souls, Lagwagon, Downset. The guys on the DIY (Do It Yourself) tours, that work outside of radio, television, and regular media.
And think or do some research before you go calling a band that influenced most of the music you claim you listen to sell outs.